Fast filtering algorithm based on vibration systems and neural information exchange and its application to micro motion robot

This paper develops a fast filtering algorithm based on vibration systems theory and neural information exchange approach. The characters, including the derivation process and parameter analysis, are discussed and the feasibility and the effectiveness are testified by the filtering performance compared with various filtering methods, such as the fast wavelet transform algorithm, the particle filtering method and our previously developed single degree of freedom vibration system filtering algorithm, according to simulation and practical approaches. Meanwhile, the comparisons indicate that a significant advantage of the proposed fast filtering algorithm is its extremely fast filtering speed with good filtering perfi^rmance. Further, the developed fast filtering algorithm is applied to the navigation and positioning system of the micro motion robot, which is a high real-time requirement for the signals preprocessing. Then, the preprocessing data is used to estimate the heading angle error and the attitude angle error of the micro motion robot. The estimation experiments illustrate the high practicality of the proposed fast filtering algorithm.

Investigation on the Radial Micro-motion about Piston of Axial Piston Pump

The limit working parameters and service life of axial piston pump are determined by the carrying ability and lubrication characteristic of its key friction pairs. Therefore, the design and optimization of the key friction pairs are always a key and difficult problem in the research on axial piston pump. In the traditional research on piston/cylinder pair, the assembly relationship of piston and cylinder bore is simplified into ideal cylindrical pair, which can not be used to analyze the influences of radial micro-motion of piston on the distribution characteristics of oil-film thickness and pressure in details. In this paper, based on the lubrication theory of the oil film, a numerical simulation model is built, taking the influences of roughness, elastic deformation of piston and pressure-viscosity effect into consideration. With the simulation model, the dynamic characteristics of the radial micro-motion and pressure distribution are analyzed, and the relationships between radial micro-motion and carrying ability, lubrication condition, and abrasion are discussed. Furthermore, a model pump for pressure distribution measurement of oil film between piston and cylinder bore is designed. The comparison of simulation and experimental results of pressure distribution shows that the simulation model has high accuracy. The experiment and simulation results demonstrate that the pressure distribution has peak values that are much higher than the boundary pressure in the piston chamber due to the radial micro-motion, and the abrasion of piston takes place mainly on the hand close to piston ball. In addition, improvement of manufacturing roundness and straightness of piston and cylinder bore is helpful to improve the carrying ability of piston/cylinder pair. The proposed research provides references for designing piston/cylinder pair, and helps to prolong the service life of axial piston pump.

Micro-motion dynamics analysis of ballistic targets based on infrared detection

The dynamic characteristics related to micro-motions, such as mechanical vibration or rotation, play an essential role in classifying and recognizing ballistic targets in the midcourse, and recent researches explore ways of extracting the micro-motion features from radar signals of ballistic targets. In this paper, we focus on how to investigate the micro-motion dynamic characteristics of the ballistic targets from the signals based on infrared (IR) detection, which is mainly achieved by analyzing the periodic fluctuation characteristics of the target IR irradiance intensity signatures. Simulation experiments demonstrate that the periodic characteristics of IR signatures can be used to distinguish different micro motion types and estimate related parameters. Consequently, this is possible to determine the micro-motion dynamics of ballistic targets based on IR detection.

Mini/Micro LED巨量转移技术研究与发展现状

对巨量转移(Mass Transfer, MT)方案和运动定位平台(Motion Positioning Platform, MPP)的研究现状及其未来发展进行了详细阐述。根据芯片转移方式,将MT方案分为精准拾取-释放技术、自组装技术、滚轴转印技术、激光剥离技术,结合芯片转移效率和良率,论述了国内外MT方案的发展过程。在此基础上,从平台支撑方式,详细介绍了机械构型、气浮构型、磁浮构型和混合构型的MPP结构及工作原理,考虑运动行程、运动定位精度等因素,比较了MPP性能的优劣。展望了MT方案和MPP技术的未来发展方向,指出基于微孔液气双态介质的激光剥离MT和具备周向小角度修正以及轴向微高度调节能力的“机械+磁浮”混合构型MPP是Mini/Micro LED芯片转移技术的研究重点。

High-Precision Wideband Phase-Derived Velocity Measurement for Micro-Motion Extraction

A phase-derived velocity measurement method is proposed in a wideband coherent system,based on a precise echo model considering the inner pulse Doppler effect caused by fast moving targets.The Cramer-Rao low band of velocity measurement precision is deduced,demonstrating the high precision of the proposed method.Simulations and out-field experiments further validate the effectiveness of the proposed method in high-precision measurement and micro-motion extraction for targets with weak reflection intensity.Compared with the long-time integration approaches for velocity measurement,the phase-derived method is easy to implement and meets the requirement for high data rate,which makes it suitable for micro-motion feature extraction in wideband systems.

人群疏散模拟仿真软件系统自主研发与应用——以Pedynamics为例

为更加精准地分析与评估公共场所突发事件下人员疏散的需求,自主研发了新一代人群疏散模拟仿真软件Pedynamics。以某地铁场景为例,比较分析Pedynamics与商业软件Pathfinder和AnyLgoic用于模拟地铁车站不同客流量下的疏散过程,并进行讨论,提出改进人群疏散效率的措施。研究结果表明:Pedynamics软件采用前后端分离的架构进行模块化开发,易于升级维护;后端采用的人群疏散计算模型结合了人群疏散动力学特别是人员有限理性路径选择行为方面的研究成果,能够真实体现行人的疏散行为特征;软件前端的场景预处理界面能够帮助用户简单、快速地基于图纸构建疏散场景,可视化及数据统计模块支持多视角查看模拟结果和疏散数据,提高工程应用的效率。研究结果可为人群疏散风险评估提供技术支持。

A Pipeline Inspection Micro Robot Based on Screw Motion Wheels

The micro robot based on screw motion wheels, which features high payload/mass ratio, fast and continuous motion, adaptation to pipe diameter or roundness variations, is suitable for locomotion and inspection inside small diameter pipelines. The robot inspection system, Tubot I, developed at Shanghai University is composed of locomotion mechanism with an inner motor, a micro CCD camera and a monitor outside the pipeline. In the paper, the kinematics and statics analyses are presented for the screw locomotion system of Tubot I. The moving characteristics are obtained from experiments on the robot prototype.

Micro-Scale Motion Precision Simulation Method for a New-Type 6-DOF Micro-Manipulation Robot

A new 6-DOF micro-manipulation robot based on 3-PPTTRS parallel mechanisms in combination with flexure hinges is proposed. The design principle of the mechanism is introduced, and the kinematics analysis method based on differentiation is used to get the (inverse) kinematics equations. Then a micro-scale motion precision simulation method is proposed according to finite element analysis (FEA), and the prediction of robot’s motion precision in design phase is realized. The simulation result indicates that the 6-DOF micro-manipulation robot can meet the design specification.

综合物探在矿山深部资源勘查中的应用

矿产资源是社会和经济发展必不可少的物质基础,目前国内多数老矿山面临已探明储量枯竭的严峻形势,现有的勘查知识和技术难以解决矿山找矿勘查所遇到的特殊难题。针对矿山找矿的特殊性,本文结合安徽省霍邱某矿区的地质及物探资料,在采矿区选取典型剖面进行重磁、微动及可控源音频大地电磁法(Controllable Source Audio Magnetotelluric Method,CSAMT)。以微动和音频大地电磁数据分析推测浅部矿体采空及塌陷区;在深部将微动勘探与重力数据结合,取长补短,通过剪切模量将微动视横波速度与地下介质密度直接联系起来,经已知矿体位置剪切模量的分布规律并结合重磁反演在300 m以深推测了两条近平行层状分布的矿体,矿体长200~250 m,最厚处约50 m;在标高100~200 m的类似S形褶皱拐点处可能为成矿有利位置;同时推测已知主矿体在底板以深还有延伸。通过本次工作,证实了在当前老矿区内,将新技术微动勘探与传统物探方法相结合,各取其长,能提高矿山深边部及外围隐伏矿床(体)定位预测的有效性,挖掘新的找矿潜力。

基于液压放大的压电微动平台设计与试验

针对传统微动平台难以满足微/纳米定位的要求,该文结合液压放大原理,提出一种基于液压放大的两自由度压电微动平台,并对其进行了结构设计。采用正交设计方法对其进行有限元双向流固耦合分析,优化了其结构参数。研制了实物样机并进行试验研究。开环控制试验结果表明,当压电驱动器输入为90μm时,压电微动平台最大输出位移为603.0μm,放大倍数约为6.7;闭环控制试验结果表明,采用分段微分、积分、比例(PID)算法能降低超调量,且响应时间、稳态时间均减小,稳态误差降低(为±0.2μm),实现了微动平台的大范围输出精密定位。

流动建构:建筑社会学视野下的城市移动咖啡馆空间实践思考

基于建筑社会学视野,对移动咖啡馆在当代流动社会中的空间实践进行探讨。将空间形式与生活模式的关联作为研究切入点,揭示流动社会中城市咖啡馆的商业模式、空间形式和文化特性转变,阐释移动咖啡馆的涌现原因与社会价值。研究发现,移动咖啡馆的当代空间实践呈现品牌化的移动咖啡车、离散状的移动咖啡店和游牧式的移动咖啡建筑三种模式,并分别以“系统集成”“自组织”与“流动建构”为特征。研究认为,移动咖啡馆的空间实践核心在于回应移动性与公共性之间的矛盾,进而提出依托“流动建构”理念和“移动建筑社会设计”策略是其灵活融入城市空间与社会生活、营造具有场所感的公共交往场所的关键。文章最后对移动咖啡馆在城市微更新场景中的应用进行了展望。

复合微多普勒信号的时频谐波分析方法

在对复合微动目标的雷达回波进行时频分析时,存在时频曲线能量难以聚焦等问题,影响目标微多普勒特征提取和分析。对此,提出了时频谐波条纹的概念以及相应时频变换方法。基于复合微动包含中心运动分量和高频运动分量的假设,首先利用样条函数拟合中心分量频率曲线,构造时频变换核函数。然后,通过参数化时频变换将时域的复合微多普勒信号转化为时频平面上的谐波条纹。所提方法相比短时傅里叶变换和伪魏格纳分布等经典方法,能够明显改善复合微动目标雷达回波时频变换的能量聚集性与杂散抑制效果,仿真验证了所提方法的有效性和对低信噪比条件的适应性。

基于半波相消的旋转叶片微动回波时频分析

在雷达探测场景中常见旋转引起的微多普勒效应,产生的微动特征与目标的几何和运动参数相关。文中从微动回波的线积分模型出发,基于半波相消的角度对旋转叶片微动回波时频特征形成机理进行了全面分析。首先在远场条件下,基于半波相消分析了旋转微动瞬时频率的形成机理,解释了其旋转微动时频特征的双端效应。进一步地,将半波相消分析扩展至近场条件,解释了近场条件下时频图双端区和镜面散射区凸显的效应。对于远场和近场条件,该文均给出了时频结果的定量解析计算方法。从图像形状和能量变化的角度对近、远场的时频特征进行分析,讨论了不同条件和参数对时频特征形状和细节的影响,基于半波相消分析将近场和远场分析统一起来,同时将线积分模型和局部散射模型联系起来。仿真实验验证了所提分析方法的正确性。

低脉冲重复频率条件下无人机微动参数提取

针对低脉冲重复频率条件下的无人机微动特征提取问题,提出一种基于原子放缩正交匹配追踪(orthogonal matching pursuit,OMP)分解的微动参数估计方法。首先,通过计算时频谱熵从无人机回波数据中筛选出具有显著微动特征的信号。其次,采用变分模态分解(variational modal decomposition,VMD)算法提取旋翼叶片的旋转频率,提出了基于原子放缩的OMP分解方法实现了对无人机旋翼叶片长度的估计。仿真实验表明所提方法相比于传统的OMP方法和VMD-OMP方法都具有明显优势。最后,采用实测数据验证了所提算法的有效性。

星载迈克尔逊干涉仪扫描角镜装调工艺研究

针对星载迈克尔逊干涉仪悬臂式扫描角镜组件装调维度多、装调精度高、检测困难等技术难点,提出了一种“向量解析+精密微动调整”方法,通过建立装调及检测基准、将角镜组件简化为空间点向量、采用“先法向后平面”的调整顺序、利用专用精密微动装置等措施,实现了空间多自由度角镜组件的高精度调整,角镜顶点位置对称度装调后达到8μm,优于0.01 mm的设计指标要求,有效提高了装调精度,缩短了装调周期。

直升机运动状态下雷达回波建模与微动特性分析

针对直升机常规雷达回波建模未考虑直升机运动时自身姿态变化对回波影响导致仿真结果与实际不符的问题,基于自由空间下旋翼叶片散射点回波模型,引入了多个参数矩阵和向量,实现直升机运动状态下雷达回波统一模型的构建.然后从理论上分析了在不同运动状态下,直升机回波微动特性变化.仿真结果验证了理论分析的正确性,表明运动状态变化对直升机雷达回波会产生影响.本文的研究对直升机目标识别及意图识别领域发展具有一定的价值.

压电微动台数据驱动迭代前馈补偿与自适应抑振

为消除压电驱动柔性微定位平台高精控制对平台不确定动力学模型的依赖性,提出了一种数据驱动无模型迭代前馈补偿和自适应陷波滤波结合的控制方法来提高平台的跟踪性能。首先,建立了数据驱动无模型迭代前馈控制器,提高系统对噪声和其他干扰的鲁棒性,同时,证明了在无模型迭代前馈作用下,连续参考输入跟踪误差的有界性和闭环系统的稳定性;其次,构建了自适应陷波滤波器来消除平台谐振的影响,对误差信号进行快速傅里叶变换,并设计谐振频率在线提取算法,实现对陷波滤波器参数的在线实时整定,来进一步提升轨迹跟踪精度;最后,利用所设计的无模型迭代前馈控制器和自适应陷波滤波器对压电微动台进行轨迹跟踪实验。实验结果表明:在跟踪三角波信号时,与单独比例-积分(Proportional Integral,PI)控制和结合自适应陷波滤波器的PI控制相比较,最大跟踪误差分别减小78.25%和70.83%,能够有效提升平台的稳定性和跟踪精度。

多宽带雷达协同目标微动周期估计方法

微动周期是区分弹头和仿形诱饵的重要特征.针对当前主要的雷达微动周期估计方法存在时间资源消耗大、对单雷达测量精度要求高、需要多宽带雷达同步观测等缺点,提出一种多宽带雷达协同目标微动周期估计方法.首先利用最小均方(LMS)算法进行目标真实尺寸估计;然后利用变尺度差频处理通过尺寸序列提取目标微动周期;最后通过仿真验证了本文方法的有效性,并探索了应用边界条件.该方法无需多宽带雷达同步观测,且在单雷达常规尺寸测量精度和时间资源消耗条件下即可准确估计目标微动周期.

PZT驱动柔性恒力装置设计与控制

不同于常规机构,恒力机构优点诸多。例如,可以吸收能量减少对对象的冲击;可以降低驱动力,间接增加位移。而且针对恒力机构研究现状发现,现有的柔性恒力机构在显微注射中的应用较少。同时利用柔性机构具有的微纳运动精度和恒力机构吸收能量减少对对象的冲击的特点,设计并制备一种锆钛酸铅基压电陶瓷(Pbbased Lanthanumdoped Zirconate Titanates,PZT)驱动恒力显微注射器,改善微注射过程中存在的阶跃冲击,提高注射量的控制精度,减少注射量因素对胚胎早期发育的影响,为显微注射技术提供可参考的数据。

繁华城区盾构工程孤石微动探测方法及爆破技术研究

微动探测技术以其快速、经济、受场地条件限制小等特点,广泛应用于浅部地质结构探测。孤石在我国南方花岗岩地区普遍存在,为解决盾构机在地层掘进时遇到大直径孤石难处理的问题,以珠海兴业快线(南段)二标为依托工程,采用微动探测技术,基于微动台阵探测地球物理探测方法,利用类空间自相关法-SPAC法从微动台阵记录中提取瑞雷波频散曲线,通过数据分析反映地层岩性变化,解释地质情况。结合钻孔探测的方式精确地获取孤石的大小及位置。采用控制性深孔爆破技术对盾构隧道范围内的孤石进行爆破预处理,优化布孔参数和装药量,根据施工现场取芯情况,爆破效果均可满足单体控制在30cm以内,破碎效果良好,完全满足盾构机掘进施工的要求。研究成果可为类似地层盾构施工工程提供借鉴和参考。